1. Field of the Invention
The present invention relates to a coffee/espresso machine comprising a milk foam generating device for cappuccino.
2. Description of the Related Art
In order to prepare cappuccino, it is desirable to design the coffee/espresso machine in such a way that on a depositing area, one cup or two cups as the collecting vessel(s) need not be repositioned when milk foam and espresso is being filled in. This simplifies and shortens the cappuccino preparing process.
For this purpose, it has been known to provide one outflow tube each for milk foam and for espresso tightly one next to the other (EP-A-0 480 928). For preparing espresso, milk foam and espresso are dispensed by this coffee/espresso machine preferably simultaneously to prepare the cappuccino within a short period of time. On the other hand, the coffee/espresso machine might instead so be adjusted that, depending on personal choice, milk foam may be dispensed either prior to or after the apportionment of espresso.—In the case of this coffee/espresso machine, however, the design of the structurally completely separated outflows and the distance thereof complicates the positioning of the cup so that the possibility of misdirecting of one of the cappuccino constituents and a danger of soiling caused thereby cannot be excluded. The cleaning of the two separate outflows is, moreover, complicated. If for each of the two outflows a rinsing duct each were provided, the structural elaboration would be significant.
In order to structurally simplify to the best a coffee/espresso machine of the kind referred to in the beginning as far as possible and to improve it as to its function, its operation and the possibility of the cleaning, it has already been known to structurally combine the coffee outflow and a milk outflow to make it one dispensing outflow unit in which the coffee outflow and the milk outflow are arranged coaxially relative to each other so that the milk outflow encircles the coffee outflow (EP 0 820 715 B1). In particular, the coffee outflow may lead into the open below the milk outflow. In this way, keeping clean of the machine should be simplified since the lower disposition of the exit of the coffee outflow avoids that it is will be clogged by milk residues. Milk remaining back in the milk outflow, however, might clog together, particularly if bars extend in the milk outflow up to a wall of the coffee outflow in order to reduce or avoid, as guide vanes, twisting of the milk and hence spilling of the milk or the milk foam. In a coffee/espresso machine having a double outflow, two coaxial arrangements each of the coffee outflow and the milk outflow may be combined together and to be connected via a distribution chamber including an espresso inflow while the foamed-up milk is separately added to the two coaxial arrangements.
If the above coffee/espresso machine, as commonly preferred, is operated so that for cappuccino preparation, first coffee/espresso flows out through the coffee outflow and subsequently milk foam through the outer coaxial milk foam outflow, the disadvantage is particularly imminent that at least part of the milk residues remaining in the milk foam outflow will cake on the coffee outflow tube during the course of the subsequent coffee/espresso outlet process and thus by the heating of the coffee outflow tube, and can only with difficulties be removed by a rinsing process.